Less invasive surgery at earlier stages of breast cancer has been correlated with higher rates of patient survival.

Duke researchers found the correlation using observational data from the California Cancer Registry to compare general health and survival rates of women who received different treatments for the first two stages of breast cancer. Common treatments include lumpectomy with radiation, where only the cancerous tissue is removed, and mastectomy, where the entire breast is removed.

Although the data, published online Monday in the journal CANCER, supports higher rates of survival for women who opted for a lumpectomy, researchers emphasized the need for further evidence.

“It’s not cause and effect,” said Scarlett Gomez, co-author of the study and professor at the Stanford School of Medicine. “However, it is provocative and prompts us to think a little bit more about what might be causing [this trend].”

Clinical trial results from 30 years ago showed that both lumpectomies and mastectomies were equally effective treatments and displayed similar long-term survival rates, said lead author Dr. Shelley Hwang, chief of breast surgery at the Duke Cancer Institute.

“The women who had mastectom[ies] were generally less healthy. They had more heart conditions and pulmonary disease and were more likely to die from cancer,” she said.

Hwang speculated that if there were a causal connection found between types of cancer treatment and survival rate, it might be caused by the decreased stress on the body in the less invasive lumpectomy.

“There could be a biologic basis in women who have less trauma and perturbation to body. The less you do to disturb the homeostasis of the biology, the better,” she said.

The study conflicts with the increasing number of women who are choosing the more invasive mastectomy surgery to treat the earlier stages of the cancer, Hwang added. Nonetheless, the researchers believe that the more invasive surgery may give patients a greater sense of control over the cancer.

“One of the things that drive women to opt for the more invasive surgery in this case is for peace of mind,” said co-author Christina Clarke, Trinity ’95 and researcher at the Cancer Prevention Institute of California. “[Patients] believe that if they get all the tissue out, they will not have to worry about it in the future.”

The subsequent daily six-week radiation treatment after the lumpectomy could also be too great a time commitment for some patients, Gomez said, adding that the more invasive one-time surgery may be appealing to women juggling work, family and other commitments.

Hwang noted that although no data proves either treatment to be more effective, it is crucial that women understand the research behind their choices before selecting a more invasive surgery.

“While [the trend] is not troubling per se, it is important for women to know when they are making that decision that it’s not based on any supportive data,” Hwang added.

The researchers hope that their findings will lead to further analysis of other data sets to determine if this increased rate of survival in lumpectomy patients holds true for other general populations. They also anticipate these results to spur more dialog between women and their care providers regarding future treatment options.